Add contiguous scope modifier

[AndreasArvidsson]

Could be used for example targeting multiple contiguous line comments.

"comment slurp comments fine"

// foo
// bar

Potential solution

I was thinking that this could be implemented around the existing scope handlers similar to how the every modifier works and just join scopes/targets based on leading and trailing delimiter ranges.

1. Get all scopes

const scopes = scopeHandler.generateScopes(...);

2. Iterate scopes and join contiguous targets

const leadingRange = leadingTarget.trailingDelimiterRange ?? leadingTarget.contentRange;
const trailingRange = trailingTarget.leadingDelimiterRange ?? trailingTarget.contentRange;
if (leadingRange.intersects(trailingRange) != null) {
    newContentRange = leadingTarget.contentRange.union(trailingTarget.contentRange);
}

Thinks to discuss

• One problem is that most leading and trailing delimiter ranges doesn't contain the eol. Eg with comment the leading range would end with the previous line and the trailing range would start with the next line. We could of course say that that is valid for merging, but it would probably make "take slurp tokens" join all tokens in the file and therefore take the entire file.
• How do we handle nested scopes?
• Do we want to support "every slurp <scope>"?

[josharian]

FWIW, in the Go ast, contiguous blocks of comments are called comment groups.

I too would like to be able to operate on comment groups.

General purpose slurp is an interesting idea. It would be useful to think of other scopes that it might apply to / other use cases where it is distinct from “every”.

[josharian]

If slurp does not ignore commenst, I guess it could be used for things like taking items between one comment and the next comment, which sounds like a reasonably common task, for example, in a list of test cases, organized into groups separated by comments.

[josharian]

Nailing down the definition of contiguous may prove to be hard. Exactly which types of other scopes can break up contiguity? And which ones don’t?

[AndreasArvidsson]

I've already suggested a definition in my code examples. I propose to define it as when two instances of the same scope have intersecting trailing/leading ranges.